SCINTIGRAPHIC ASSESSMENT OF THE METACARPOPHALANGEAL AND METATARSOPHALANGEAL JOINTS OF HORSES WITH JOINT PAIN

Our aims were to evaluate the pattern of radiopharmaceutical uptake in horses with lameness related to the metacarpophalangeal and/or metatarsophalangeal joint and compare the results with similar information from sound horses. It was hypothesized that there would be a difference in radiopharmaceutical uptake between the lame and contralateral limb in unilaterally lame horses and that there would be a difference between lame and sound horses. Nuclear scintigraphic images of 43 horses with forelimb lameness and 30 horses with hindlimb lameness were evaluated. In all horses lameness was improved by intraarticular analgesia of the joint, or by perineural analgesia of the palmar/plantar (at the junction of the proximal 3/4 and the distal 1/4 of the metacarpal/metatarsal regions) and palmar/plantar metacarpal/metatarsal nerves. All images were assessed subjectively and a quantitative image analysis was performed by drawing a vertical line profile through the center of each joint in the lateral images and using region of interest analysis in both lateral and dorsal/plantar images. Ratios of radiopharmaceutical uptake were compared for each region between lame and contralateral limbs in unilaterally lame horses and between lame and control horses. There was a significant difference in the ratio of radiopharmaceutical uptake in the proximal aspect of the proximal phalanx between lame and nonlame forelimbs in unilaterally lame horses and in both lame and contralateral limbs of lame horses compared with control horses for the regions of the distal aspect of the third metacarpal/metatarsal bone and the proximal sesamoid bones. However, the profile analysis was of limited clinical value.     

ULTRASONOGRAPHIC DIAGNOSIS OF COXOFEMORAL SUBLUXATION IN HORSES

The clinical and ultrasonographic features of seven horses with coxofemoral subluxation are presented. Affected horses included five adult geldings (11–20 years), one large pony (6 years) and a 3-month-old filly. All were lame at the walk except for the pony with grade 3/5 lameness. Lameness was acute in all horses, but three horses progressed after initial improvement. Crepitus, muscle atrophy, and pelvic asymmetry were inconsistent findings. Ultrasonographic diagnosis of subluxation required dynamic visualization of femoral head displacement from the acetabulum while placing weight on the affected limb and subsequent replacement into its normal position upon limb resting. Acetabular rim fractures and joint effusion were visible regardless of weight bearing status in six horses each. No fractures were identified in the pony; the only patient with a good outcome. Six horses had a poor outcome with severe chronic lameness, four of which were euthanized. Postmortem ventrodorsal radiographs obtained in two horses confirmed subluxation only on extended limb projections, but not on hip-flexed projections. Acetabular rim fractures were not visible radiographically in either horse but were confirmed at necropsy. Subluxation was due to an elongated but intact ligament of the head of the femur in both horses. Osteoarthrosis was evident ultrasonographically, radiographically, and at necropsy. Dynamic ultrasonography was readily performed in the standing horse and produced diagnostic images with a low frequency curvilinear transducer. The apparent poor prognosis for horses with subluxation and acetabular fracture illustrate the importance of this imaging technique to identify affected horses.     

Interannual variability in growth of larval and juvenile walleye pollock Theragra chalcogramma in the western Gulf of Alaska, 1983–91

Interannual variability in growth of larval walleye pollock Theragra chalcogramma was examined from 1983 to 1991 and of juveniles from 1985 to 1990. ANCOVA was used to assess differences in population growth rates, and an alternate method was developed to examine variations between annual length-at-age data and average 'expected' values over different age groupings. For larvae, the years 1986, 1987, 1989 and 1990 had higher than average length-at-age, and 1988 and 1991 had lower than average values. Relationships between growth and SST and larval density were not clear. A tentative relationship between copepod nauplii abundance and larval length-at-age was noted. The consequence of larval growth to larval mortality, late larval abundance or recruitment was not clear. We conclude that larval mortality rates are highly variable and tend to mask effects of moderate variability in growth on later abundance. For juveniles, 1987 had significantly lower than average length-at-age and 1988 had higher than average values. Although there are few years of data, they tend to support the importance of juvenile growth in the recruitment process. Conditions for the large 1988 year class are documented and discussed, including warm SST, calm winds, relatively low larval growth rates, low abundances of potential predators on larvae, low larval mortality rates, and high juvenile growth rates.     

Bilateral Ureteroileostomy and Perineal Urinary Diversion in Dogs

The urinary bladder was excised, and the ureters were implanted into an isolated segment of distal jejunum and ileum in three experimental dogs. The isolated bowel loop was drawn through the pelvic canal within the external anal sphincter to exit ventral to the anus. The dogs were evaluated for urinary continence, urinary tract infection, and renal function for up to 6 months postoperatively.
Urinary continence did not return. Continuous urine leakage caused perineal scalding. The cutaneous openings of the isolated bowel loops developed strictures. Serum creatinine and urea nitrogen concentrations did not increase. Excretory urography and retrograde radiographic studies of the bowel loop were performed periodically. Unilateral hydronephrosis was observed in two dogs 2 weeks postoperatively. The remainder of the excretory urograms were normal. Ureteral reflux was observed commonly on retrograde contrast studies. Positive bacterial cultures were obtained from all bowel loops and kidneys at necropsy. Alpha-streptococcus, Escherichia coli , and Proteus spp. were isolated most frequently. Mild pyelitis was seen in histopathologic examination of the kidneys after necropsy. Urothelium replaced bowel mucosa near the site of ureteral implantation.
This method of urinary diversion is not satisfactory for clinical use.     

Talocalcaneal Luxation An Anatomic and Clinical Study

Talocalcaneal luxation in dogs was studied by anatomic dissection of the talocalcaneal joint in cadavers and review of five clinical cases. The integrity of the talocalcaneal joint was maintained by two strong ligaments traversing the tarsal sinus between the two bones. The joint was found to be a low motion joint. Luxation in clinical cases was not always apparent on standard radiographic views. Three dogs were treated surgically with a screw inserted in lag fashion from talus to calcaneus. One luxation was treated surgically with figure-of-eight orthopedic wires and one was treated with external coaptation. Four dogs returned to their previous levels of function without clinically detectable lameness.     

Gastric Conduit Urinary Diversion in Normal Dogs Part II, Hypochloremic Metabolic Alkalosis

Gastric conduit urinary diversion was performed in 10 dogs after complete cystectomy. Four dogs were euthanatized on day 30 because of hypochloremic metabolic alkalosis and renal failure. Hematologic and biochemical changes in six dogs evaluated for 120 days were compatible with hypochloremic metabolic alkalosis. The continuous loss of hydrochloric acid from the gastric conduit resulted in significant increases in arterial blood pH, PaCO2, anion gap, TCO2, and the concentration of HCO3-. There were significant decreases in PaO2 and the serum concentrations of chloride and potassium. Deterioration of renal function resulted in all dogs. It was concluded that hypochloremic metabolic alkalosis makes gastric conduit urinary diversion unsatisfactory for clinical use in dogs.     

Investigation of the host ranges of the leaf blotch pathogens of onion (Cladosporium allii-cepae) and leek (C. allii)

Inoculation of a range of Allium species and two non-alliaceous species with isolates of Cladosporiumallii-cepae and C. allii , obtained from onion and leek, respectively, demonstrated that the two pathogens had distinct host ranges. Conidia of C. allii-cepae, applied either dry or in aqueous suspension, infected A. altaicum, A. fistulosum (Japanese bunching onion), A. cepa (bulb onion), A. cepa var. ascalonicum (shallot), A. galanthum, A. pskemense and A. vavilovii . Dry conidia of C. allii applied at a high concentration caused atypical necrosis on A. altaicum, A. fistulosum, A. cepa var. ascalonicum, A. galanthum, A. pskemense, A. vavilovii, A. sativum (garlic), A. ampeloprasum and A. porrum (leek). Only A. ampeloprasum and A. porrum became typically infected following inoculation with conidia applied dry at low concentration or in aqueous suspension. Isolates of C. allii from leek failed to infect A. vineale, the type host. The length of conidia of a single isolate of C. allii-cepae varied significantly on different Allium spp.     

Radiology in tortoises, terrapins and turtles as an aid to diagnosis

The exposure factors, choice of film and screens, positioning of the patient and alterations in beam direction are described as are two types of contrast media for the gastro-intestinal tract. Methods for the use of dental films and macro-radiography are also given. Four diseases of chelonians, nutritional osteodystrophy, pneumonia, oedema and a ruptured bladder are described together with the associated radiographs and radiological interpretation.     

Lower Extremity Amputation and Application of a Prosthetic Device in a 1-Month-Old Calf

During correction of a dystocia, a fracture occurred involving the right third and fourth metacarpus of a calf. Application of a plaster cast resulted in devitalization of the limb. The distal limb was amputated, and a prosthetic device capable of periodic lengthening was fitted. The calf was able to walk well 1 month following surgery.